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A tube assembly with a through-wall fracture at a brazed bracket joint was investigated to determine the cause for component failure. The product was made from 1008 cold-rolled steel sheet, shaped into 12.7-mm diameter tubing and seam welded axially. The material was manufactured and shipped as a straight tube. During component manufacture, an approximately 650-mm length of the tubing was bent at two locations to form an “S”-shaped component. Four different mounting brackets were then brazed onto it. The fully assembled part fractured adjacent to one of the brackets, within the “S”-bend of the tube assembly, prior to entering service. Failure analysis revealed that premature fracture was related to excessive infusion of copper into the tube wall along grain boundaries. Metallography of tube sections demonstrated exposure of the joint to excessively high temperature, sufficient to cause partial dissolution of some grains. Scanning electron microscopy and energy dispersive spectroscopy revealed that the braze metal appears to be a copper-manganese (Cu-Mn) base alloy. The widespread intergranular dispersion of braze metal in the tube wall adjacent to the brazed bracket indicated excessive temperature exposure and liquid metal embrittlement. Possible causes for the anomalies observed at the bracket braze failure site are discussed.